Upgraded today, fixed up a vocal track this arvo for the vocalist to go back and learn before final tracking, and was simply stunned at how much better 4 is than 2. I've gone from editor 2 to 4 studio, only just scratched the surface of what it is capable of doing, and already thinking the $149 is worth every penny.
Just my opinion of course, but if you are still thinking of this, go for it if you can afford it.
Dave.